A wide variety of different types of wheelchairs are produced to service the different needs of the user. These are often referred to as K-1, K-2, K-3, K-4, K-5, K-9, E1161, E1230, E1231, E1232, E1233, E1234, E1235, E1236, E1237, E1238, E1239 and E1240 wheelchairs based on the Medicare reimbursement K-code categories and Healthcare Common Procedure Coding System (HCPCS codes). A K-1 or K0001 wheelchair is a basic institutional wheelchair. These chairs generally have a non-adjustable steel frame construction, weighing approximately 41 to 45 pounds, and a seat to floor height of 19 to 21 inches. A K-2 or K0002 wheelchair is the same as the K-1 wheelchair with the exception of having a lower seat to floor height approximately 17 to 18 inches and shorter foot plate extension tubes. The K-3 or K0003 wheelchair is light weight ranging from 28 to 36 pounds with a seat to floor height of 19 to 21 inches and has a larger seat with size of approximately 20 inches as opposed to the standard 16 to 18 inch seat width. A K-4 or K0004 wheelchair is also light weight ranging from 26 to 34 pounds and has a number of frame adjustments that may be incorporated into the construction as well as an adjustable axle plate. These chairs are also available in a number of standard seat widths including 14, 16, 18 and 20 inches and have a variety of seat to floor heights ranging from 17 to 21 inches. K-5 or K0005 and K-9 wheelchairs are custom designed lightweight or ultra-lightweight wheelchairs. These wheelchairs are custom fit to the user and provide items such as an adjustable axle plate, rigid or folding construction, a variety of suspension types, a variety of castor size options for controlling turning radius on variable terrain, adjustable seat and back angles, different back height options, a variety of seat width and seat to floor heights ranging from 17 to 21 inches. These chairs can weight from 14 to 30 pounds depending on type of construction.
All of these types of wheelchairs provide the user with options for comfort during use. However, the location of the larger diameter rear wheel makes it difficult for the user to transfer from one wheelchair to another if needed. A number of unique wheelchair configurations have been developed to attempt to overcome this problem. One of these options raises the seat above the top of the larger diameter rear wheel. However, this raises the center of gravity of the wheelchair making it easier to tip over. Another option uses smaller diameter sized wheels. In some of these constructions all four wheels are of the smaller diameter size. Unfortunately, this can make it difficult for the user to traverse different types of terrain and can remove the user's ability to independently propel the wheelchair. Another provides removable side rails. Unfortunately this does not remove the larger diameter rear wheel from the transfer path.
Consequently, there is still a need in the industry for a wheelchair device that provides an unobstructed path when the user desires to transfer out of the wheelchair.